| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce on-resistance of a bidirectional switch comprising two MOS type transistors having a shared drain in a trench gate structure. <P>SOLUTION: On an N-type well layer 2, a plurality of trenches 3 are formed. Then, a P-type body layer 6 is formed in every other line in the N-type well layer 2 held between the plurality of trenches 3. In the plurality of P-type body layers 6, an N<SP POS="POST">+</SP>-type first source layer 7 and an N<SP POS="POST">+</SP>-type second source layer 9 are alternately formed. A first gate electrode 5a is formed in each of a pair of trenches 3 holding the N<SP POS="POST">+</SP>-type first source layer 7 therebetween, and a second gate electrode 5b is formed in each of a pair of trenches 3 holding the N<SP POS="POST">+</SP>-type second source layer 9 therebetween. The N-type well layer 2 held between a sidewall on the opposite side of the P-type body layer 6 side of the trench 3 where the first gate electrode 5a is formed and the similar sidewall where the second gate electrode 5b is formed is turned to an N-type drain layer 11a as an electric field relaxation layer. The N-type drain layer 11a is turned to a current route where an on-state current of the bidirectional switch flows. <P>COPYRIGHT: (C)2012,JPO&INPIT |
